mount.h revision 53975
1/*
2 * Copyright (c) 1989, 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	@(#)mount.h	8.21 (Berkeley) 5/20/95
34 * $FreeBSD: head/sys/sys/mount.h 53975 1999-12-01 02:09:30Z mckusick $
35 */
36
37#ifndef _SYS_MOUNT_H_
38#define _SYS_MOUNT_H_
39
40#include <sys/ucred.h>
41
42#ifndef KERNEL
43#if !defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE)
44#include <sys/stat.h>
45#endif /* !_POSIX_C_SOURCE */
46#endif /* !KERNEL */
47
48#include <sys/queue.h>
49#include <sys/lock.h>
50
51typedef struct fsid { int32_t val[2]; } fsid_t;	/* file system id type */
52
53/*
54 * File identifier.
55 * These are unique per filesystem on a single machine.
56 */
57#define	MAXFIDSZ	16
58
59struct fid {
60	u_short		fid_len;		/* length of data in bytes */
61	u_short		fid_reserved;		/* force longword alignment */
62	char		fid_data[MAXFIDSZ];	/* data (variable length) */
63};
64
65/*
66 * file system statistics
67 */
68
69#define MFSNAMELEN	16	/* length of fs type name, including null */
70#define	MNAMELEN	80	/* length of buffer for returned name */
71
72struct statfs {
73	long	f_spare2;		/* placeholder */
74	long	f_bsize;		/* fundamental file system block size */
75	long	f_iosize;		/* optimal transfer block size */
76	long	f_blocks;		/* total data blocks in file system */
77	long	f_bfree;		/* free blocks in fs */
78	long	f_bavail;		/* free blocks avail to non-superuser */
79	long	f_files;		/* total file nodes in file system */
80	long	f_ffree;		/* free file nodes in fs */
81	fsid_t	f_fsid;			/* file system id */
82	uid_t	f_owner;		/* user that mounted the filesystem */
83	int	f_type;			/* type of filesystem */
84	int	f_flags;		/* copy of mount exported flags */
85	long    f_syncwrites;		/* count of sync writes since mount */
86	long    f_asyncwrites;		/* count of async writes since mount */
87	char	f_fstypename[MFSNAMELEN]; /* fs type name */
88	char	f_mntonname[MNAMELEN];	/* directory on which mounted */
89	long    f_syncreads;		/* count of sync reads since mount */
90	long    f_asyncreads;		/* count of async reads since mount */
91	short	f_spares1;		/* unused spare */
92	char	f_mntfromname[MNAMELEN];/* mounted filesystem */
93	short	f_spares2;		/* unused spare */
94	long    f_spare[2];		/* unused spare */
95};
96
97/*
98 * Structure per mounted file system.  Each mounted file system has an
99 * array of operations and an instance record.  The file systems are
100 * put on a doubly linked list.
101 */
102LIST_HEAD(vnodelst, vnode);
103
104struct mount {
105	TAILQ_ENTRY(mount) mnt_list;		/* mount list */
106	struct vfsops	*mnt_op;		/* operations on fs */
107	struct vfsconf	*mnt_vfc;		/* configuration info */
108	struct vnode	*mnt_vnodecovered;	/* vnode we mounted on */
109	struct vnode	*mnt_syncer;		/* syncer vnode */
110	struct vnodelst	mnt_vnodelist;		/* list of vnodes this mount */
111	struct lock	mnt_lock;		/* mount structure lock */
112	int		mnt_flag;		/* flags shared with user */
113	int		mnt_kern_flag;		/* kernel only flags */
114	int		mnt_maxsymlinklen;	/* max size of short symlink */
115	struct statfs	mnt_stat;		/* cache of filesystem stats */
116	qaddr_t		mnt_data;		/* private data */
117	time_t		mnt_time;		/* last time written*/
118	u_int		mnt_iosize_max;		/* max IO request size */
119};
120
121/*
122 * User specifiable flags.
123 */
124#define	MNT_RDONLY	0x00000001	/* read only filesystem */
125#define	MNT_SYNCHRONOUS	0x00000002	/* file system written synchronously */
126#define	MNT_NOEXEC	0x00000004	/* can't exec from filesystem */
127#define	MNT_NOSUID	0x00000008	/* don't honor setuid bits on fs */
128#define	MNT_NODEV	0x00000010	/* don't interpret special files */
129#define	MNT_UNION	0x00000020	/* union with underlying filesystem */
130#define	MNT_ASYNC	0x00000040	/* file system written asynchronously */
131#define	MNT_SUIDDIR	0x00100000	/* special handling of SUID on dirs */
132#define	MNT_SOFTDEP	0x00200000	/* soft updates being done */
133#define	MNT_NOSYMFOLLOW	0x00400000	/* do not follow symlinks */
134#define	MNT_NOATIME	0x10000000	/* disable update of file access time */
135#define	MNT_NOCLUSTERR	0x40000000	/* disable cluster read */
136#define	MNT_NOCLUSTERW	0x80000000	/* disable cluster write */
137
138/*
139 * NFS export related mount flags.
140 */
141#define	MNT_EXRDONLY	0x00000080	/* exported read only */
142#define	MNT_EXPORTED	0x00000100	/* file system is exported */
143#define	MNT_DEFEXPORTED	0x00000200	/* exported to the world */
144#define	MNT_EXPORTANON	0x00000400	/* use anon uid mapping for everyone */
145#define	MNT_EXKERB	0x00000800	/* exported with Kerberos uid mapping */
146#define	MNT_EXPUBLIC	0x20000000	/* public export (WebNFS) */
147
148/*
149 * Flags set by internal operations,
150 * but visible to the user.
151 * XXX some of these are not quite right.. (I've never seen the root flag set)
152 */
153#define	MNT_LOCAL	0x00001000	/* filesystem is stored locally */
154#define	MNT_QUOTA	0x00002000	/* quotas are enabled on filesystem */
155#define	MNT_ROOTFS	0x00004000	/* identifies the root filesystem */
156#define	MNT_USER	0x00008000	/* mounted by a user */
157#define	MNT_IGNORE	0x00800000	/* do not show entry in df */
158
159/*
160 * Mask of flags that are visible to statfs()
161 * XXX I think that this could now become (~(MNT_CMDFLAGS))
162 * but the 'mount' program may need changing to handle this.
163 * XXX MNT_EXPUBLIC is presently left out. I don't know why.
164 */
165#define	MNT_VISFLAGMASK	(MNT_RDONLY	| MNT_SYNCHRONOUS | MNT_NOEXEC	| \
166			MNT_NOSUID	| MNT_NODEV	| MNT_UNION	| \
167			MNT_ASYNC	| MNT_EXRDONLY	| MNT_EXPORTED	| \
168			MNT_DEFEXPORTED	| MNT_EXPORTANON| MNT_EXKERB	| \
169			MNT_LOCAL	| MNT_USER	| MNT_QUOTA	| \
170			MNT_ROOTFS	| MNT_NOATIME	| MNT_NOCLUSTERR| \
171			MNT_NOCLUSTERW	| MNT_SUIDDIR	| MNT_SOFTDEP	| \
172			MNT_IGNORE \
173			/*	| MNT_EXPUBLIC */)
174/*
175 * External filesystem command modifier flags.
176 * Unmount can use the MNT_FORCE flag.
177 * XXX These are not STATES and really should be somewhere else.
178 */
179#define	MNT_UPDATE	0x00010000	/* not a real mount, just an update */
180#define	MNT_DELEXPORT	0x00020000	/* delete export host lists */
181#define	MNT_RELOAD	0x00040000	/* reload filesystem data */
182#define	MNT_FORCE	0x00080000	/* force unmount or readonly change */
183#define MNT_CMDFLAGS	(MNT_UPDATE|MNT_DELEXPORT|MNT_RELOAD|MNT_FORCE)
184/*
185 * Internal filesystem control flags stored in mnt_kern_flag.
186 *
187 * MNTK_UNMOUNT locks the mount entry so that name lookup cannot proceed
188 * past the mount point.  This keeps the subtree stable during mounts
189 * and unmounts.
190 */
191#define MNTK_UNMOUNT	0x01000000	/* unmount in progress */
192#define	MNTK_MWAIT	0x02000000	/* waiting for unmount to finish */
193#define MNTK_WANTRDWR	0x04000000	/* upgrade to read/write requested */
194
195/*
196 * Sysctl CTL_VFS definitions.
197 *
198 * Second level identifier specifies which filesystem. Second level
199 * identifier VFS_VFSCONF returns information about all filesystems.
200 * Second level identifier VFS_GENERIC is non-terminal.
201 */
202#define	VFS_VFSCONF		0	/* get configured filesystems */
203#define	VFS_GENERIC		0	/* generic filesystem information */
204/*
205 * Third level identifiers for VFS_GENERIC are given below; third
206 * level identifiers for specific filesystems are given in their
207 * mount specific header files.
208 */
209#define VFS_MAXTYPENUM	1	/* int: highest defined filesystem type */
210#define VFS_CONF	2	/* struct: vfsconf for filesystem given
211				   as next argument */
212
213/*
214 * Flags for various system call interfaces.
215 *
216 * waitfor flags to vfs_sync() and getfsstat()
217 */
218#define MNT_WAIT	1	/* synchronously wait for I/O to complete */
219#define MNT_NOWAIT	2	/* start all I/O, but do not wait for it */
220#define MNT_LAZY	3	/* push data not written by filesystem syncer */
221
222/*
223 * Generic file handle
224 */
225struct fhandle {
226	fsid_t	fh_fsid;	/* File system id of mount point */
227	struct	fid fh_fid;	/* File sys specific id */
228};
229typedef struct fhandle	fhandle_t;
230
231/*
232 * Export arguments for local filesystem mount calls.
233 */
234struct export_args {
235	int	ex_flags;		/* export related flags */
236	uid_t	ex_root;		/* mapping for root uid */
237	struct	ucred ex_anon;		/* mapping for anonymous user */
238	struct	sockaddr *ex_addr;	/* net address to which exported */
239	int	ex_addrlen;		/* and the net address length */
240	struct	sockaddr *ex_mask;	/* mask of valid bits in saddr */
241	int	ex_masklen;		/* and the smask length */
242	char	*ex_indexfile;		/* index file for WebNFS URLs */
243};
244
245/*
246 * Structure holding information for a publicly exported filesystem
247 * (WebNFS). Currently the specs allow just for one such filesystem.
248 */
249struct nfs_public {
250	int		np_valid;	/* Do we hold valid information */
251	fhandle_t	np_handle;	/* Filehandle for pub fs (internal) */
252	struct mount	*np_mount;	/* Mountpoint of exported fs */
253	char		*np_index;	/* Index file */
254};
255
256/*
257 * Filesystem configuration information. One of these exists for each
258 * type of filesystem supported by the kernel. These are searched at
259 * mount time to identify the requested filesystem.
260 */
261struct vfsconf {
262	struct	vfsops *vfc_vfsops;	/* filesystem operations vector */
263	char	vfc_name[MFSNAMELEN];	/* filesystem type name */
264	int	vfc_typenum;		/* historic filesystem type number */
265	int	vfc_refcount;		/* number mounted of this type */
266	int	vfc_flags;		/* permanent flags */
267	struct	vfsconf *vfc_next;	/* next in list */
268};
269
270struct ovfsconf {
271	void	*vfc_vfsops;
272	char	vfc_name[32];
273	int	vfc_index;
274	int	vfc_refcount;
275	int	vfc_flags;
276};
277
278/*
279 * NB: these flags refer to IMPLEMENTATION properties, not properties of
280 * any actual mounts; i.e., it does not make sense to change the flags.
281 */
282#define	VFCF_STATIC	0x00010000	/* statically compiled into kernel */
283#define	VFCF_NETWORK	0x00020000	/* may get data over the network */
284#define	VFCF_READONLY	0x00040000	/* writes are not implemented */
285#define VFCF_SYNTHETIC	0x00080000	/* data does not represent real files */
286#define	VFCF_LOOPBACK	0x00100000	/* aliases some other mounted FS */
287#define	VFCF_UNICODE	0x00200000	/* stores file names as Unicode*/
288
289#ifdef KERNEL
290
291#ifdef MALLOC_DECLARE
292MALLOC_DECLARE(M_MOUNT);
293#endif
294extern int maxvfsconf;		/* highest defined filesystem type */
295extern int nfs_mount_type;	/* vfc_typenum for nfs, or -1 */
296extern struct vfsconf *vfsconf;	/* head of list of filesystem types */
297
298/*
299 * Operations supported on mounted file system.
300 */
301#ifdef __STDC__
302struct nameidata;
303struct mbuf;
304#endif
305
306struct vfsops {
307	int	(*vfs_mount)	__P((struct mount *mp, char *path, caddr_t data,
308				    struct nameidata *ndp, struct proc *p));
309	int	(*vfs_start)	__P((struct mount *mp, int flags,
310				    struct proc *p));
311	int	(*vfs_unmount)	__P((struct mount *mp, int mntflags,
312				    struct proc *p));
313	int	(*vfs_root)	__P((struct mount *mp, struct vnode **vpp));
314	int	(*vfs_quotactl)	__P((struct mount *mp, int cmds, uid_t uid,
315				    caddr_t arg, struct proc *p));
316	int	(*vfs_statfs)	__P((struct mount *mp, struct statfs *sbp,
317				    struct proc *p));
318	int	(*vfs_sync)	__P((struct mount *mp, int waitfor,
319				    struct ucred *cred, struct proc *p));
320	int	(*vfs_vget)	__P((struct mount *mp, ino_t ino,
321				    struct vnode **vpp));
322	int	(*vfs_fhtovp)	__P((struct mount *mp, struct fid *fhp,
323				    struct vnode **vpp));
324	int	(*vfs_checkexp) __P((struct mount *mp, struct sockaddr *nam,
325				    int *extflagsp, struct ucred **credanonp));
326	int	(*vfs_vptofh)	__P((struct vnode *vp, struct fid *fhp));
327	int	(*vfs_init)	__P((struct vfsconf *));
328	int	(*vfs_uninit)	__P((struct vfsconf *));
329};
330
331#define VFS_MOUNT(MP, PATH, DATA, NDP, P) \
332	(*(MP)->mnt_op->vfs_mount)(MP, PATH, DATA, NDP, P)
333#define VFS_START(MP, FLAGS, P)	  (*(MP)->mnt_op->vfs_start)(MP, FLAGS, P)
334#define VFS_UNMOUNT(MP, FORCE, P) (*(MP)->mnt_op->vfs_unmount)(MP, FORCE, P)
335#define VFS_ROOT(MP, VPP)	  (*(MP)->mnt_op->vfs_root)(MP, VPP)
336#define VFS_QUOTACTL(MP,C,U,A,P)  (*(MP)->mnt_op->vfs_quotactl)(MP, C, U, A, P)
337#define VFS_STATFS(MP, SBP, P)	  (*(MP)->mnt_op->vfs_statfs)(MP, SBP, P)
338#define VFS_SYNC(MP, WAIT, C, P)  (*(MP)->mnt_op->vfs_sync)(MP, WAIT, C, P)
339#define VFS_VGET(MP, INO, VPP)	  (*(MP)->mnt_op->vfs_vget)(MP, INO, VPP)
340#define VFS_FHTOVP(MP, FIDP, VPP) \
341	(*(MP)->mnt_op->vfs_fhtovp)(MP, FIDP, VPP)
342#define	VFS_VPTOFH(VP, FIDP)	  (*(VP)->v_mount->mnt_op->vfs_vptofh)(VP, FIDP)
343#define VFS_CHECKEXP(MP, NAM, EXFLG, CRED) \
344	(*(MP)->mnt_op->vfs_checkexp)(MP, NAM, EXFLG, CRED)
345
346#include <sys/module.h>
347
348#define VFS_SET(vfsops, fsname, flags) \
349	static struct vfsconf fsname ## _vfsconf = {		\
350		&vfsops,					\
351		#fsname,					\
352		-1,						\
353		0,						\
354		flags						\
355	};							\
356	static moduledata_t fsname ## _mod = {			\
357		#fsname,					\
358		vfs_modevent,					\
359		& fsname ## _vfsconf				\
360	};							\
361	DECLARE_MODULE(fsname, fsname ## _mod, SI_SUB_VFS, SI_ORDER_MIDDLE)
362
363#include <net/radix.h>
364
365#define	AF_MAX		33	/* XXX */
366
367/*
368 * Network address lookup element
369 */
370struct netcred {
371	struct	radix_node netc_rnodes[2];
372	int	netc_exflags;
373	struct	ucred netc_anon;
374};
375
376/*
377 * Network export information
378 */
379struct netexport {
380	struct	netcred ne_defexported;		      /* Default export */
381	struct	radix_node_head *ne_rtable[AF_MAX+1]; /* Individual exports */
382};
383
384extern	char *mountrootfsname;
385
386/*
387 * exported vnode operations
388 */
389int	dounmount __P((struct mount *, int, struct proc *));
390int	vfs_setpublicfs			    /* set publicly exported fs */
391	  __P((struct mount *, struct netexport *, struct export_args *));
392int	vfs_lock __P((struct mount *));         /* lock a vfs */
393void	vfs_msync __P((struct mount *, int));
394void	vfs_unlock __P((struct mount *));       /* unlock a vfs */
395int	vfs_busy __P((struct mount *, int, struct simplelock *, struct proc *));
396int	vfs_export			    /* process mount export info */
397	  __P((struct mount *, struct netexport *, struct export_args *));
398struct	netcred *vfs_export_lookup	    /* lookup host in fs export list */
399	  __P((struct mount *, struct netexport *, struct sockaddr *));
400int	vfs_allocate_syncvnode __P((struct mount *));
401void	vfs_getnewfsid __P((struct mount *));
402dev_t	vfs_getrootfsid __P((struct mount *));
403struct	mount *vfs_getvfs __P((fsid_t *));      /* return vfs given fsid */
404int	vfs_modevent __P((module_t, int, void *));
405int	vfs_mountedon __P((struct vnode *));    /* is a vfs mounted on vp */
406int	vfs_rootmountalloc __P((char *, char *, struct mount **));
407void	vfs_unbusy __P((struct mount *, struct proc *));
408void	vfs_unmountall __P((void));
409int	vfs_register __P((struct vfsconf *));
410int	vfs_unregister __P((struct vfsconf *));
411extern	TAILQ_HEAD(mntlist, mount) mountlist;	/* mounted filesystem list */
412extern	struct simplelock mountlist_slock;
413extern	struct nfs_public nfs_pub;
414
415/*
416 * Declarations for these vfs default operations are located in
417 * kern/vfs_default.c, they should be used instead of making "dummy"
418 * functions or casting entries in the VFS op table to "enopnotsupp()".
419 */
420int	vfs_stdmount __P((struct mount *mp, char *path, caddr_t data,
421		struct nameidata *ndp, struct proc *p));
422int	vfs_stdstart __P((struct mount *mp, int flags, struct proc *p));
423int	vfs_stdunmount __P((struct mount *mp, int mntflags, struct proc *p));
424int	vfs_stdroot __P((struct mount *mp, struct vnode **vpp));
425int	vfs_stdquotactl __P((struct mount *mp, int cmds, uid_t uid,
426		caddr_t arg, struct proc *p));
427int	vfs_stdstatfs __P((struct mount *mp, struct statfs *sbp, struct proc *p));
428int	vfs_stdsync __P((struct mount *mp, int waitfor, struct ucred *cred,
429		struct proc *p));
430int	vfs_stdvget __P((struct mount *mp, ino_t ino, struct vnode **vpp));
431int	vfs_stdfhtovp __P((struct mount *mp, struct fid *fhp, struct vnode **vpp));
432int	vfs_stdcheckexp __P((struct mount *mp, struct sockaddr *nam,
433	   int *extflagsp, struct ucred **credanonp));
434int	vfs_stdvptofh __P((struct vnode *vp, struct fid *fhp));
435int	vfs_stdinit __P((struct vfsconf *));
436int	vfs_stduninit __P((struct vfsconf *));
437
438#else /* !KERNEL */
439
440#include <sys/cdefs.h>
441
442__BEGIN_DECLS
443int	fstatfs __P((int, struct statfs *));
444int	getfh __P((const char *, fhandle_t *));
445int	getfsstat __P((struct statfs *, long, int));
446int	getmntinfo __P((struct statfs **, int));
447int	mount __P((const char *, const char *, int, void *));
448int	statfs __P((const char *, struct statfs *));
449int	unmount __P((const char *, int));
450int	fhopen __P((const struct fhandle *, int));
451int	fhstat __P((const struct fhandle *, struct stat *));
452int	fhstatfs __P((const struct fhandle *, struct statfs *));
453
454/* C library stuff */
455void	endvfsent __P((void));
456struct	ovfsconf *getvfsbyname __P((const char *));
457struct	ovfsconf *getvfsbytype __P((int));
458struct	ovfsconf *getvfsent __P((void));
459#define	getvfsbyname	new_getvfsbyname
460int	new_getvfsbyname __P((const char *, struct vfsconf *));
461void	setvfsent __P((int));
462int	vfsisloadable __P((const char *));
463int	vfsload __P((const char *));
464__END_DECLS
465
466#endif /* KERNEL */
467
468#endif /* !_SYS_MOUNT_H_ */
469